If I read the “Members” section of the multipolygon wiki page right, multipolygons should not have other multipolygons as members. However, there are about 65 of these in Sweden, and 11 in Greater London (which are the database extracts I happen to have within easy reach).
Should these be fixed?
If not, is there a definition of what it means? In particular, if a multipolygon A has another multipolygon B as an inner, and B has a hole, does the interior of the hole ( = the finite part of the exterior of B) belong to the interior of A (as would be the case if the interior of B was simply subtracted from the interior of A)?
How does whatever software that renders the standard “carto” map handle this? Is there a write-up somewhere? (Because, let’s face it, the de-facto rule for what is valid is “whatever renders on the main map”; anyone trying to use other rules is facing an uphill battle.)
22 posts - 8 participants
Ce sujet de discussion accompagne la publication sur https://community.openstreetmap.org/t/multipolygons-as-members-of-multipolygons/102212